Heavy marijuana users are likely to fail a drug test after abstaining from the herb for several weeks, according to a new study published in the journal Drug and Alcohol Dependence. While experts have known for sometime that the way marijuana metabolizes in the body is nothing short of unpredictable, the latest research finds that THC detection times are still traceable in the blood and urine of regular users two weeks after the last toke.
To come to this conclusion, researchers at the University of Duisburg-Essen in Germany set out to explore the sobering results of stoners who claimed to use marijuana on a daily basis for the past six months. Each of the participants were then asked to submit to a series of blood and urine tests in an attempt to gauge the duration for which it took them to yield a negative result.
Interestingly, researchers found that over half of the participants still tested positive for THC by the end of the study. Of that percentage, 16 individuals continued to test at the 50 nanograms of THC cap for urine drug screens for 16 days. A marijuana user typically tests between 51 to 141 ng/mL in the event of a failed urinalysis.
Yet, for the everyday pot smoker who is forced to submit to a blood test, researchers say the presence of THC can be noticeably present after abstaining for several weeks. In fact, after testing the study participants’ blood, over half revealed a small trace of marijuana — 1 nanogram of THC per milliliter.
The majority of blood tests look for THC in a range somewhere between 1.3 to 6.4 ng/mL, with the failed result being in the higher spectrum. For example, in Colorado, a person can be arrested for stoned driving if they register over 5 ng/mL.
The results of the latest study are consistent with previous research that has determined that marijuana can be present in a person’s system for months following the last date of consumption.
Of course, there are several variables involved with determining how long it will take a person to test clean for marijuana. Frequency of use is a factor, as well as body fat. Someone with a higher percentage of body fat can be expected to take longer to detox from the doobie than the average person. However, it is important to understand that since everyone has varying body chemistries, there can be unforeseen exceptions to the rules.